I don' think that they would have added a shot to the tv spot that is not close to finish on the trailer, sure they'll edit the cloaking a bit more but what we saw is the basic structure of the CGI, so there's not so much to edit. It kinda looked like the cloak was glowing when turned off... anyone else saw it like that?
I think it's pretty "21st century", meaning it suits the movie. What I saw in the trailer of the Predator decloaking looked good, can't say more. I must say though, the best cloaking effects in my opinion were delivered in AvP 1 (as much as I hate the AvP-Movies).